1. Technical Field
The present invention generally relates to the wireless communication field and, particularly to an amplitude shift keying (ASK) demodulator and a radio frequency identification (RFID) system using the same.
2. Description of the Related Art
With the rapid developments of the requirement for wireless communication as well as broadband wireless networks, radio frequency identification systems have become a very hot topic in recent years. The radio frequency identification systems aim at shortcomings of traditional contact systems and transmit digital data using radio waves, so that transponders thereof can interchange data with readers without the need of direct contact. As a result, the device wear and tear caused by direct contact is avoided and the convenience for use is improved. Furthermore, if the radio frequency identification systems can be combined with the current display industry and directly integrated into display devices, applications thereof would become more popular and widespread.
Therefore, in one aspect, how to design a demodulator adapted to receive low-amplitude input signals and thus suitable for wireless related systems (e.g., radio frequency identification systems) working with low-amplitude input signals; in another aspect, how to design a radio frequency identification system which is suitable for being incorporated into a display device manufactured by a high threshold voltage process of low temperature poly-silicon (LTPS); both of the above-mentioned aspects are problems needed to be urgently solved at present.